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 <?php session_start(); ?>
 <!DOCTYPE html>
 <html>
     <head>
         <meta charset="utf-8">
         <title></title>
         <?php include "includes.php"; ?>
     </head>
     <body>
         <?php include "header.php" ?>
         <br />
         <div class = "container">
             <form class = "form-signin" method="post">
                <input type="text" class="form-control" name="username" placeholder="Администраторско име" required></br>
                <input type="password" class="form-control" name="password" placeholder="Парола" required> <br />
                <button class="form-control" type="submit" name="login">Влез</button>
             </form>
        </div>
     </body>
 </html>
 <?php
 //Start creating admin user login functionality
 if (isset($_POST['login'])) {

     $username = $_POST['username'];
     $password = $_POST['password'];

    //Check if inputs are empty
    if (empty($username) || empty($password)) {
        header("Location: index.php?login=empty");
        exit();
    } else {
        $sql = "SELECT * FROM users WHERE username='$username' AND password='$password'";
        $result = mysqli_query($conn, $sql);
        $resultCheck = mysqli_num_rows($result);

        if ($resultCheck < 1) {
            header("Location: index.php?login=error");
            exit();
        } else {
            if ($row = mysqli_fetch_assoc($result)) {
                //De-hashing the password
                $hashedPasswordCheck = password_verify($password, $row['password']);
                if ($hashedPasswordCheck == false) {
                    header("Location: index.php?login=error");
                    exit();
                } elseif ($hashedPasswordCheck == true) {
                    //Log in the admin user here
                    $_SESSION['usernameId'] = $row['id'];
                    $_SESSION['username'] = $row['username'];
                    header("Location: index.php?login=success");
                    exit();
                }
            }
        }
    }
} else {
    header("Location: index.php?login=error");
    exit();
}
?>